Coupler for a top rail of playpen



FIG. 1 is a perspective view of coupler for a top rail of playpen showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof; and,

FIG. 8 is an environmental perspective view and FIG. 9 is a reduced scale environmental perspective view with the broken line showing of environment being for illustrative purposes only and forming no part of the claimed design. 

The ornamental design for coupler for a top rail of playpen, as shown and described. 